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File:OptischerTelegraf.jpg|right|200px|thumb|Replica of Claude Chappe's optical telegraph on the Litermont near Nalbach, Germany '''Telegraphy''' (from Greek language|Greek: τῆλε ''wikt:tele-|têle'', "at a distance" and γράφειν ''wikt:-graphy|gráphein'', "to write") is the long-distance transmission of textual or symbolic (as opposed to verbal or audio) messages without the physical exchange of an object bearing the message. Thus flag semaphore|semaphore is a method of telegraphy, whereas pigeon post is not. Telegraphy requires that the method used for encoding the message be known to both sender and receiver. Such methods are designed according to the limits of the signalling Media (communication)|medium used. The use of smoke signals, beacons, Heliograph|reflected light signals, and flag semaphore signals are early examples. In the 19th century, the harnessing of...
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